The invention relates to a method for calibrating a pressure sensor or a flow sensor at a rotary pump supporting the pulsating heart.
It is common practice to use an intracardiac rotary pump for supporting the heart activity. WO 98/43688 describes an intracardiac blood pump where the control of the pumping operation is carried out as a function of the measuring signal supplied by a pressure measuring means. On the basis of the measured pressure value the delivery rate of the pump can be determined. The pump casing made from a tube comprises in one case a pressure differential sensor which determines the pressure differential between the outlet pressure and the inlet pressure of the pump. The pump inlet is provided with a cannula which extends through the aortic valve in the case of a left-ventricular pump. This cannula causes additional losses which are, to a large extent, proportional to the pump speed and whose effects can be mathematically taken into account. An essential error source is the occurrence of a drift at the pressure sensor. Such a drift requires recalibration of the pressure sensor and/or determination of a correction value.